The cathedral of Monreale, next to the Palatine Chapel in Palermo and the Cathedral of Cefalu, It is the culmination, construction of a century Norman, continental and insular.
In it converge syncretically constructive experiences, that starting to Cluny in the tenth century, continue with the dell'abbaziale edification of Bernay and subsequently the Trinitè , St. Nicolas
e St. E'tienne in Caen, combining at Miletus, these architectures with those dell'abbaziale of Montecassino and experimenting in the cathedrals of Catania and Messina impregnated new types of Sicilian regionalism and new Norman experimentalism, (v. Lessay Normandia – Some).
Observed from outside the Cathedral of King William II, It is divided into three main volumes characteristic of the Western churches in Latin cross: The longitudinal basilican body with three naves, transept, and the area triabsidata. These volumes are added to the west: two bell towers which clamp the pillared entrance porch (esonartece) surmounted by a triangular gable, according to the typical pattern of Normandy churches. The dell'esonartece surfaces were decorated with scenes from the life of the Blessed Vergine Maria.
The large front door coated with bronze panels, by Bonanno da Pisa, It was placed in 1185.
At the crossing of the transept and the nave rises, over the other buildings: the lantern square containing the solea, not a dome, but from a double-pitched roof, as the underlying coverage of the nave. The latter abuts with the ridge, the bottom center line of the central wont window..
The interior of the body basilican, It is as already mentioned, divided into three aisles by a double row composed of nine columns burial remains surmounted by capitals of obvious classical origin . Each of the side aisles is wide one-third of the central. The capitals are in turn connected with the overlying pulvini with abaci to book according to a typically Norman form. The abaci evidently have different thickness for joining the various heights of the columns, mutually different in order to put at the same level all the tax plans of the ogival arches.
The particular geometric shape of the latter cooperates to the centering of the weights of the structures on the column axis which in this way, not undergo accentrici loads that would compromise the stability. A technical device that allows to make more agile and resistant internal structures, characteristic of Byzantine-Islamic architecture of that period, subsequently adopted with some variations, Gothic cathedrals. The arches go far beyond the usual levels Normans characterized by walkers overhanging the aisles, whose lancet windows or trifore in Monreale disappear, to give way to the vast mosaic fields (more than six thousand square meters)that covering structures, the dematerialized with their reflected light. One has the impression that the cathedral was built with light, rather than with stone.
The nave is covered with a wooden structure A gable, while the aisles are with a roof to a single flap. The roofs were rebuilt after about thirty years after the devastating fire in 1811devastò much of the chancel .
The precious decorations of the trusses and ceilings, probably redone based on previous medieval drawings, They blend perfectly with the wall mosaics.
The prospect, drawn by the double of the columns of the nave theory, It extends with the structures that crosses in the sanctuary, Order optically each element or architectural mosaic, in one convergence towards Christ Pantocrator, ingeniously and harmoniously proportioned in the curved surface of the apse in a stereoscopic effect.
Architecture and iconography are made according to a single predetermined design in every detail.
Al chancel is accessed through the arcs which determine the various sectors. The presbytery, for amplitude, It interacts with the Cassinese abbey, very slight protrusions with respect to the body basilical unlike Norman transepts with very pronounced transverse arms, with respect to the heads of the aisles.
But this configuration, at least within, It is restored by the introduction of a four-pillared (typically Byzantine module), that divides the chancel in a double transept with inner arms obvious:
The first intercepts the axis of the central nave, determining the raised square of the solea where the headquarters of the altar; the second contains in internal alignment, the central apse with those side, according to the scheme Norman - cluniacense. By conforming also, the areas of the prosthesis and the diakonikon, as independent chapels, according to the types of small churches of Normandy in one classroom, ( v. The then newly). outside, plan, the three apses take the usual form jaggy, (stepped), with pronounced central. It is, however, show, some substantial differences with the Byzantine and contemporary Norman components: the lantern at the intersection of the transept and the prolongation of the nave, while riconducendosi to tetrastyle module centric Byzantine, It is surmounted by a dome, but closed with a double-pitched roof. The apse areas are covered with cross vaults with the exception of the apse that is not pierced by the usual three windows (sometimes, circular, as in some churches the Normandy), to give more space inside the immense figure of the Pantocrator.
The surveyors planimetric relationships between the various components are dictated by strict criteria and proportional to a metric system whose unit of measurement is equivalent to the Islamic cubit (circa 42 cm v. PLANIM attached).
At the equal of the great Christian basilica buildings, the Cathedral was preceded by a large rectangular enclosure with garden and central well for the use of pilgrims called: Paradiso, closed by side porches concluded by narthex. It was reached by a front door practiced in western perimeter defended by walls and towers.